1. Field of the Invention
The present invention relates to a transmission device of a handheld electronic device, more particularly, a transmission device capable of cooling a handheld electronic device.
2. Description of the Prior Art
Functions of handheld electronic devices are becoming more powerful as technology progresses; even so, more heat will be given off as the handheld electronic device executes its functions. If heat generated from internal components of the handheld electronic device is not properly released, the functional operation and speed will be affected. In addition, overheating of the internal components can even cause damage to the device. However, in order to satisfy the needs of the consumers, the development of handheld electronic devices will continue towards miniature designs. The problem of cooling the handheld electronic device given a limited space, as mentioned-above has become an important research topic for manufacturers.
In general, there are two methods of cooling electrical products: the active cooling method and the passive cooling method. The active cooling method is implemented by adding a cooling device such as a fan to the electrical product. The passive cooling method utilizes a heat releasing metal plate that is attached to the internal component of the electrical product. In the handheld electronic device, such as a mobile phone, if the active cooling method is employed by installing a fan in the mobile phone, then the noise generated from the fan when the fan blades are spinning will negatively affect a user when having a conversation. Furthermore, the bearings of the fan are easily damaged; therefore, maintenance cost of the handheld electronic device increases as well. If non-active cooling such as a metal plate is attached to the internal component of the handheld electronic device then a reasonable surface area of the metal plate is needed to cool the device. The weight of the metal plate will increase the volume and the weight of the handheld electronic device.
Please refer to FIG. 1. FIG. 1 illustrates a diagram of a charger capable of cooling a conventional notebook computer (please refer to U.S. Pat. No. 6,571,340). The charger 100 comprises a cooling system 110, for generating airflow to cool the notebook computer. However, the arrangement of the internal components of the handheld electronic device is denser than the arrangement of the internal components of the notebook computer. Because of the increased density, if the speed of the airflow is not sufficiently fast, then the effect of cooling will decrease due to the limited space in the handheld electronic device. Furthermore, heat is also generated when the handheld electronic device transmits data, and the conventional charger 100 is unable to provide a function of data transmission and cooling at the same time.